This invention relates to the field of practical mechanics, and specifically to an arrangement for facilitating the use of portable routers. A router of this sort comprises a high speed motor with a vertical shaft carrying at its lower end a chuck to receive the standard shank of any of a plurality of bits, and a handle base supporting the motor on the surface of a work piece and providing axial adjustment to determine the depth of the end of the bit below the work surface.
Such routers are in wide spread use and it is generally known that auxiliary means must be provided to assist the use in guiding the router with respect to the work. The base of the router, which may be substantially round, is not large enough to give a desirable off-set or displacement from the cutter axis for fences or guides secured directly thereto, and resort has been had to sub-bases or to transversely extending rods to support fences at a greater off-set for work on large surfaces. Fences and guides of various sorts are known, and are described in the handbooks supplied to the purchasers of routers.
One of the uses for a portable router is to trim the edge of a overlay laminate even with the edge of a counter or other top to which it is adhered. A known way of doing this is by use of a special bit called a "flush trimmer" which carries at its free end a ball bearing pilot, of the same diameter as the bit itself, for contacting the edge of the top below the laminate and thus positioning the bit transversely to give the desired finished surface.